Wetting resistant materials and articles made therewith

Abstract

Ceramic materials with relatively high resistance to wetting by various liquids, such as water, are presented, along with articles made with these materials. The oxide materials described herein as a class typically contain one or more of ytterbia (Yb 2 O 3 ) and europia (Eu 2 O 3 ). The oxides may further contain other additives, such as oxides of gadolinium (Gd), samarium (Sm), dysprosium (Dy), or terbium (Tb). In certain embodiments the oxide, in addition to the ytterbia and/or europia, further comprises lanthanum (La), praseodymium (Pr), or neodymium (Nd).

1. A material comprising:
 an oxide comprising from about 60 mole % to about 99 mole % gadolinia and at least about 1 mole % ytterbia, wherein the oxide is B-type monoclinic and wherein the oxide has up to about 25 atomic percent of its total cation content as tetravalent cations. 
 
     
     
       2. The material of  claim 1 , wherein the oxide comprises up to about 30 mole percent ytterbia. 
     
     
       3. The material of  claim 2 , wherein the oxide comprises at least about 70 mole percent gadolinia. 
     
     
       4. The material of  claim 1 , wherein the oxide further comprises europia. 
     
     
       5. The material of  claim 4 , wherein the oxide further comprises samaria, dysprosia, or terbia. 
     
     
       6. The material of  claim 2 , wherein the oxide comprises x mole percent of ytterbia and 100-x mole percent of gadolinia, wherein x is up to about 30 mole percent. 
     
     
       7. The material of  claim 1 , wherein the oxide is transparent to electromagnetic radiation of at least one type selected from the group consisting of ultraviolet radiation, visible light, and infrared radiation.